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Back stab

Percutaneous vertebroplasty for severe back pain

Mark Otto Baerlocher, MD
Resident in the Radiology Program at the University of Toronto in Ontario

Murray R. Asch, MD FRCPC
Director of Interventional Radiology at the Lakeridge Health Corporation in Oshawa, Ont

Correspondence to: Susitna Banerjee, 47 Great Oak Private, Ottawa, ON K1G 6P7; telephone 613 733-4364; e-mailsbane059{at}uottawa.ca

Vertebroplasty is an image-guided procedure during which cement is injected into weak or collapsed vertebrae.¹ It is used to treat acute severe back pain that arises from osteoporotic or benign vertebral compression fractures, vertebral osteonecrosis, vertebral body hemangiomas, vertebral metastasis, and multiple myelomas when the pain does not resolve with conservative treatment (bed rest, analgesics, external back bracing, and physical therapy). Vertebroplasty is also used as an adjuvant therapy for preoperative, peri-operative, or intraoperative percutaneous stabilization for spinal decompressive procedures.^1–3

It is important to be aware of vertebroplasty, as fractures from osteoporosis are common and the clinical consequences are serious. Untreated vertebral fractures can cause pain, disability, and neurologic deficits. Multiple vertebral compression fractures can cause the spine to shorten or deform leading to postural instability and reduced ventilatory capacity.⁴ Vertebroplasty should be considered for patients who fail to benefit from conservative management.

Kyphoplasty is a procedure that uses a balloon to restore the height of the vertebral body. To date, no scientific study has demonstrated a difference in efficacy between vertebroplasty and kyphoplasty.⁵ As this is the case, this article will discuss vertebroplasty only.

Before vertebroplasty is performed, physicians should take a careful history, do a thorough physical examination, and obtain radiographs to correlate the area of pain with the level of the compression fracture. Focal neurologic deficits or myelopathy must also be excluded. Cross-sectional imaging, such as magnetic resonance imaging or computed tomography, should be done to exclude severe compromise of the spinal canal, to assess the integrity of the posterior vertebral elements, and to exclude other causes of back pain. Magnetic resonance imaging and nuclear medicine bone scans are valuable methods for estimating the severity of fractures.¹

Procedure

During the procedure, patients lie prone and are moderately sedated with medications, such as midazolam and fentanyl citrate. Strict adherence to sterile technique is essential to reduce the risk of infection in the injected cement. Local anesthetics are used to numb the skin, paraspinal muscles, and periosteum. High-quality fluoroscopic guidance is used so that a transpedicular or parapedicular approach can be used to insert an 11- to 13-gauge needle into the vertebral body. Bone cement (polymethylmethacrylate) in liquid form is injected through the needle under real-time fluoroscopic control to ensure appropriate dispersal within the vertebral body. Patients then lie supine for 1 hour to allow the cement to solidify and are assessed for relief of back pain, neurologic deficits or new chest pain before same-day discharge. Pain relief is usually immediate but might take 72 hours.¹

Quality of evidence

Ovid MEDLINE was searched from January 1966 to August 2006 using the word vertebroplasty with the following MeSH search terms therapy, OR treatment outcome, OR costs, OR benefits, OR side effects, OR cost-benefit. Of 252 articles found, 205 remained after the search was limited to the English language. Most of the remaining articles were excluded on account of title, abstract, and key words if it was evident that they had fewer than 20 patients, did not use a clinical measure as outcome, concerned kyphoplasty, were review articles, or were duplicate studies. Nine articles remained and were analyzed. A similar secondary search was conducted using PubMed. Of the 574 English-language articles found with the term vertebroplasty, 4 were chosen and analyzed. References of all articles were scanned for other relevant papers. The data we present have come from large case studies and 1 nonrandomized controlled study that provided level II evidence dating back to the year 2000.

Outcomes of vertebroplasty

Several large case studies have examined the outcomes of percutaneous vertebroplasty for compression fractures and tumours (Table 1). The research done by McGraw et al,⁶ Diamond et al,⁷ Anselmetti et al,⁸ Winking et al,⁹ Zoarski et al,¹⁰ and Kobayashi et al¹¹ has shown that, after vertebroplasty, 60% to 100% of patients had substantial pain relief, 34% to 91% of patients used fewer analgesics, and 29% to 100% of patients had improved mobility. The studies done by Do et al,¹² Vogl et al,³ Prather et al,¹³ Purkayastha et al,² Winking et al,⁹ Evans et al,¹⁴ McKiernan et al,¹⁵ and Grados et al¹⁶ showed that, after vertebroplasty, pain scores on a 10-point visual analogue scale decreased from 8.9 to 0.05, analgesic use scores decreased from 2.93 to 0, and ambulation impairment scores decreased from 7.2 to 0.11. Diamond et al⁷ found that 29 patients who underwent percutaneous vertebroplasty had 43% fewer days of hospitalization than inpatients treated with conservative methods.

The primary benefits of vertebroplasty are less pain, less analgesic use, better mobility, and shorter recovery times, which mean less need for nursing and rehabilitation care. With vertebroplasty, there is less chance of complications arising from vertebral compression fractures, such as deep venous thrombosis, osteoporosis acceleration, height loss, respiratory problems, gastrointestinal troubles, and emotional and social issues arising from severe pain.¹

Contraindications

Contraindications to vertebroplasty include asymptomatic compression fractures of the vertebral body, vertebra plana, retropulsed bone fragments or tumours, active infection, uncorrectable coagulopathy, allergy to the bone cement or opacification agent, severe cardiopulmonary disease, pregnancy, or pre-existing radiculopathy.^2–4,7,17

Cautions

Before the procedure, imaging is important. Recent spine radiographs, computed tomography scans, magnetic resonance imaging scans, and nuclear medicine bone scans are recommended to ensure an accurate understanding of the anatomy and to assess the age of fracture sites. For patients with acute fractures, it is best to defer the procedure for at least 4 weeks to allow for spontaneous healing and resolution of pain. Direct physical examination under fluoroscopy is also essential to confirm that the site of pain corresponds with the location of the fracture. Usually, single-session treatment is limited to 3 or fewer vertebral levels. Some researchers have suggested that patients younger than 65 should avoid vertebroplasty because their bones might heal spontaneously, and the long-term effects of vertebroplasty are unknown.^1,3,17

Complications

Minor complications due to vertebroplasty have been reported. Recent studies have shown that short-term complications occurred in 0.5% to 76% of procedures (Table 1). Transient pain was noted in 0.5% to 16.3% of patients.^6,8,11,14,16 Asymptomatic cement leakage was noted in 1% to 54% of patients^3,9,10 and in 3% to 76% of injections.^2,8,11,15,16 Hematoma occurred in 0.6% to 1% of patients,^7,11 asymptomatic pulmonary embolism was seen in 3.5% to 5% of patients,^8,16 transient nausea was noted in 1% of patients,¹¹ and transient fever was noted in 8% of patients.¹⁶ Fractures were seen in 2% to 7% of patients^7,14,15 and in 16% of injections.^10,11 Grados et al¹⁶ reported that there was a slightly increased risk of vertebral fractures in the area of a cemented vertebra (odds ratio 2.27, 95% confidence interval 1.11 to 4.56). Other transient minor complications included allergic contact dermatitis from the cement and pneumothorax in patients with thoracic lesions.^1,4

Rare but serious complications of vertebroplasty have been reported. Anselmetti et al⁸ described 1 patient (1.7% of patients studied) who experienced a subcutaneous paravertebral hematoma that required hospitalization and blood derivative transfusion and took 1 week to resolve. Other serious complications include spinal cord compression, neurologic complications (such as optic neuritis), paradoxical embolization of the cerebral artery from cement leaking into epidural veins, or cement embolization via the paravertebral venous plexus to the lungs causing pulmonary infarction and clinical symptoms.^{1,12,13,17,18} In rare cases, extruded cement requires decompressive surgery.¹ In most cases where neurologic symptoms occurred after cement extravasation, the procedures were not performed using high-quality real-time fluoroscopic imaging. Finally, the polymethylmethacrylate cement releases heat during polymerization that can damage osteocytes. These osteocytes are not resorbed, which can lead to bone degeneration later in life.⁴

Other treatments

Conservative measures should be attempted before treating with vertebroplasty. Conservative treatments include bed rest, analgesics, external back bracing, and physical therapy. If conservative treatments fail, some evidence indicates that nerve-root injection should be considered for patients with radicular pain. Kim et al¹⁹ treated 58 patients with painful osteoporotic vertebral fractures by injecting their nerve roots with lidocaine, bupivacaine, and methylprednisolone. The injections were repeated at 2-week intervals to a maximum of 3 injections or until symptoms improved. Mean pain scores decreased from 85.0 before treatment to 24.9 at 1 month and to 14.1 at 6 months after treatment. The authors suggested that nerve-root injections should be considered before percutaneous vertebroplasty or operative intervention for patients with vertebral fractures and radicular pain.¹⁹

Future of vertebroplasty

Several advances can improve the vertebroplasty technique. First, biodegradable or bioactive materials that augment bone are being researched, as they can help induce new bone growth.¹ Combining vertebroplasty with kyphoplasty, where the inflation of a high-pressure balloon is used to restore the height and shape of the vertebral body and then the cavity is filled with cement, could be helpful.¹ The long-term effects of bone cement need to be studied; for example, the potential risk of new fractures in adjacent vertebrae must be further investigated. Finally, randomized controlled trials are needed to compare vertebroplasty with conservative treatment.

Availability in Canada

A substantial number of radiologists (interventional radiologists, neuroradiologists, and musculoskeletal radiologists) do percutaneous vertebroplasty in Canada. An unpublished survey of the Canadian Interventional Radiology Association showed that, in 2005, of a total of 75 responding interventional radiologists, 59% were at centres that performed vertebroplasty with a 2- to 8-week wait time from time of referral to time of procedure. Of the respondents not performing vertebroplasty, 28% anticipated beginning to perform the procedure 1 year after the time of the survey. A partial list of radiologists across Canada who perform vertebroplasty and their contact information is available from www.cfpc.ca/cfp/2007/Jul/_images/vol53-jul-clinic-alreview-banerjee-list.png. Any radiology department can be contacted to find out whether someone there performs vertebroplasty.

Conclusion

Vertebroplasty is an effective treatment for symptomatic vertebral compression fractures arising from osteoporosis, hemangiomas, malignancies, and vertebral osteonecrosis that have not been cured by conservative treatment. Patients have reported less pain, less use of analgesics, improved mobility, and better quality of life after vertebroplasty. Vertebroplasty should not be used for patients with asymptomatic compression fractures of the vertebral body, vertebra plana, ret-ropulsed bone fragments or tumour, active infection, pre-existing radiculopathy, uncorrectable coagulopathy, allergy to cement or the opacification agent, severe cardiopulmonary disease, pregnancy, or pre-existing radiculopathy. Complications include pain, asymptomatic bone cement leakage, hemorrhage, nausea, fever, nerve-root irritation, rib or vertebral posterior element fractures, contact dermatitis, osteocyte degeneration, and pneumothorax. Rare but possible serious complications include severe hematomas, neurologic complications, paradoxical cerebral arterial embolization, and cement embolization causing pulmonary infarct and clinical symptoms.

Canadian Interventional Radiologists who currently perform percutaneous vertebroplasty and can be contacted for referrals Contact information given is how physicians prefer to be reached

PROVINCE CITY NAME ADDRESS CONTACT INFORMATION Alberta Calgary Dr Bevan Frizzell Dr Will Morrish Dr Roy Park Foothills Medical Centre Department of Diagnostic Imaging 1403—29 St NW Calgary, AB T2N 2T9 Telephone 403 944–1969 Fax 403 944–4011 Alberta Calgary Dr Drew Schemmer Peter Lougheed Centre 3500—26 Ave NE Calgary, AB T1Y 6J4 Telephone 403 943–4040 E-mailendorad{at}telus.net Alberta Edmonton Dr Rob Ashforth Dr Rob Lambert Dr Suki Dhillo Dr Richard Owen University of Alberta Hospital 10351—96 St NW Edmonton, AB T5H 2H5 Telephone 780 407–1210 Fax 780 407–1202 Alberta Red Deer Dr Chris Siwak Central Alberta Medical Imaging Services 4312—54th Ave Red Deer, AB T4N 4M1 Telephone 403 343–6172 Fax 403 343–6159 E-mailcsiwak{at}hotmail.com British Columbia Vancouver Dr Jason Clement St Paul’s Hospital 1081 Burrard St Vancouver, BC V6Z 1Y6 Telephone 604 806–8006 Fax 604 806–8437 British Columbia Vancouver Dr Peter Munk Dr Stephen Ho Dr Manraj Heran Dr Gerald Legiehn University of British Columbia Department of Radiology 3350—950 W 10th Ave Vancouver, BC V5Z 1M9 Telephone 604 875–4165 Fax 604 875–4319 E-mailradiolog{at}interchange.ubc.ca British Columbia Victoria Dr Doug Connell Royal Jubilee Hospital Site 1952 Bay St Victoria, BC V8R 1J8 Manitoba Winnipeg Dr Greg McGinn Dr Scott Sutherland Health Sciences Centre Department of Radiology 820 Sherbrook St Winnipeg, MB R3A 1R9 Telephone 204 787–1328 Fax 204 787–2080 New Brunswick Moncton Dr Luc Francoeur Dr Vikash Prasad The Moncton Hospital Department of Medical Imaging 135 MacBeath Ave Moncton, NB E1C 6Z8 Telephone 506 857–5280 Fax 506 857–5298 Nova Scotia Halifax Dr Eric Versnick QEII Health Sciences Centre Department of Radiology 1796 Summer St Halifax, NS B3H 3A7 Telephone 902 473–4512 Ontario Hamilton Dr M. L. Ellins Dr DiPanka Sarma Dr Arlene Franchetto Dr Hema Choudur Hamilton General Hospital Diagnostic Imaging 237 Barton St E Hamilton, ON L8L 2X2 Telephone 905 527–4322, extension 46521 Fax 905 527–5761 E-mailmary.ellins{at}gmail.com anddipanka{at}hotmail.com Ontario London Dr Andrew Leung Dr David Pelz Dr Donald Lee University Hospital Department of Radiology 339 Windermere Rd London, ON N6A 5A5 Telephone 519 663–3203 Fax 519 663–8803 E-mailandrew.leung{at}lhsc.on. ca;pelz{at}uwo.ca; orleefam{at}sympatico.ca Ontario Oshawa Dr Murray Asch Lakeridge Health Oshawa Interventional Radiology 1 Hospital Court Oshawa, ON L1G 2B9 Telephone 905 576–8711 extension 3497 Fax 905 721–4770 E-mailmasch{at}lakeridgehealth.on.ca Ontario Ottawa Dr Cheemun Lum Ottawa Hospital—Civic Campus Department of Diagnostic Imaging 1053 Carling Ave Ottawa, ON K1Y 4E9 Telephone 613 798–5555, extension 19582 Ontario Peterborough Dr Dan Bourgeois Peterborough Regional Health Centre Diagnostic Imaging 1 Hospital Dr Peterborough, ON K9J 7C6 Telephone 705 867–5039 Fax 705 743–1313 E-maildbourgeois{at}prhc.on.ca Ontario Toronto Dr Bruce G. Gray Dr Walter Montanera Dr Dominic Rosso St Michael’s Hospital 30 Bond St Toronto, ON M5B 1W8 Telephone 416 864–5792 Fax 416 864–5380 Ontario Toronto Dr Seon Kyu Lee Toronto Western Hospital University Health Network Suite 3MC-429, 399 Bathurst St Toronto, ON M5T 2S8 Telephone 416 603–5800, extension 5562 Fax 416 603–4257 E-mailseonkyu.lee{at}uhn.on.ca Ontario Windsor Dr Jack Speirs Hôtel Dieu Grace Hospital Department of Diagnostic Imaging 1030 Ouellette Ave Windsor, ON N9A 1E1 Telephone 519 973–4411, extension 3524 E-mailjspeirs{at}chdgh.org Quebec Gatineau Dr Martin Lepage Dr Christopher Place Hull Hospital/CSSS Gatineau Radiology Department 116 Lionel-Émond Blvd Gatineau, QC J8Y 1W7 Telephone 819 595–6028 Fax 819 595–6076 Quebec Lévis Dr André Renaud Hôtel-Dieu de Lévis Département de radiologie 143, rue Wolfe Lévis, QC G6V 3Z1 Telephone 418 835–7101 Fax 418 835–7169 Quebec Longueuil Dr Maxime Tremblay Dr Pierre Bergeron Hôpital Pierre-Boucher 1333 Jacques Cartier Est Longueuil, QC J4M 2A5 Telephone 450 468–8157 Fax 450 468–8165 Quebec Montreal Dr Carlos I. Torres Royal Victoria Hospital Department of Radiology 687 Pine Ave W Montreal, QC H3A 1A1 Telephone 514 934–1934, extension 42862 E-mailcarlos.torres{at}muhc.mcgill.ca Quebec Montreal Dr François Guilbert Dr Daniel Roy Dr Alain Weill Dr Jean Raymond CHUM—Hôpital Notre-Dame Département de radiologie 1560, rue Sherbrooke Est Montreal, QC H2L 4M1 Telephone 514 890–8000, extension 25115 Fax 514 412–7547 Quebec Montreal Dr Donatella Tampieri Montreal Neurological Hospital and Institute, MUHC McGill University Telephone 514 398–1908 or514 398–1910 Fax 514 398–7213 E-maildonatella.tampieri{at}muhc.mcgill.ca Quebec St-Jérôme Dr Philippe René Hôtel-Dieu de St-Jérôme Hospital 290, rue Montigny St-Jérôme, QC J7Z 5T3 Telephone 450 421–8200, extension 2310 Quebec Trois-Rivières Dr Jean-Philippe Bolduc Dr Stéphan Servant CHRTR—Pavillon Ste-Marie 1991, boul du Carmel Trois-Rivières, QC G8Z 3R9 Telephone 819 697–3333 Saskatchewan Regina Dr Ashok K. Verma Dr Shantilal M. Lala Regina General Hospital 1440—14th Ave Regina, SK S4P 0W5 Telephone 306 766–3715 Fax 306 766–4385

EDITOR’S KEY POINTS Percutaneous vertebroplasty as a treatment for vertebral compression fractures is increasingly available in Canada. Studies have shown considerable benefit in pain relief and shorter recovery times, and complications tend to be minor and transient. Serious complications have generally occurred when procedures were not performed under high-quality, real-time fluoroscopic imaging. There are still some unanswered questions. Should patients younger than 65 have this procedure? What is the risk of new fractures adjacent to the treatment site? What are the long-term effects of percutaneous vertebroplasty? More randomized controlled trials are needed.

 

Footnotes

This article has been peer reviewed.

Competing interests

None declared

References

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